Well it’s been a while but I have now progressed a little further and have a 2001 camry long block with the direct injection, and a Gen3 sump. 
I also have a complete ST215 engine (in pieces) with full OEM gasket kit which I could also rebuild at some stage. I got this mainly for the inlet manifold, and also to be able to match things up and see what is interchangeable during the build. I know I could use the sump and crank sensor but that would mean I can’t re-assemble and reuse the st215 engine.
 
I am now trying to determine part numbers required. I know I need the SC7451 CP pistons, but in terms of conrods what options are there nowadays? I know Pauter have the TOY-220-550-1380F and Crower have B93754B-4, but are any other manufacturers (such as Eagle) able to do some for a non custom price. 
 
I would like NOT to ground down the 5S celica crank I have for the following reasons:
Stronger crank as no need to ground anything off journals.
No cost of getting ground journals to 3S size.
Easier/cheaper to source another crank if something unfortunate should happen.
 
However on the other side of coin:
Less off the shelf conrod choices. 
5S Pauter are around US$450 more expensive than 3S Eagle.
Less choice of 5S conrod bearings, I could only find Clevite(CB-1639P) or King (CR4135AM). I’m leaning towards King as some of the bigger builds have used them.
 
Out of curiosity, what rod bolts come with Pauter, Pauters own?
 
For others reference, I am also looking at using the following:
ARP 3SGTE Main Studs (203-5404)
ARP 3SGTE Head Studs (203-4204)
Toyota OEM 3SGTE Full Gasket Kit (04111-74541)
5SFE Rear Main Seal (90080-31021)
5SFE Water pump with 3S inlet hose bracket that has the bolt that holds the dip stick to it.
5SFE Oil pump with 3S Oil pump Gear
3S Gen 3 Timing belt to match the Oil pump gear, probably HKS
Apexi 1.1mm head gasket (814-T201)
 

I just used 3s eagle in mine. Plenty of people run them without any problems. I can't remember exactly how much the machine work on the crank was but only around $200.
I went with ACL race bearings.

Can anyone confirm that a 5S water pump will work with a 3S timing belt. I was under the impression that a 91-93 5S water pump (16100-79185-83) will be fine. I thought the difference was to do with the number of teeth, but it is also the teeth profile. 3S timing belt is a round profile, while the 5S is more a V profile. The wheel also looks larger on the 3S pump than the 5S.
 
For those that have done a 5S build, what did you use? Anyone used a 5S waterpump?
Here are the 3S pump teeth

 and the 5S pump teeth. Looks to be a non genuine, which I removed off my 2001 engine.

 

I have genuine Toyota (aisin) water pumps off 5s with 23 teeth and off 3sge 1998 year model (gen3) with 22 teeth both on bench and they both have the rounded profile to conform to the 3sge belt.
Hope this is of some help.

Would you happen to know the part number of that 5S pump with rounded profile?
But still not sure I could use it as it has 1 extra tooth. I found this picture on ebay of a 16100-79185-83 pump which has V profile, but haven't been able to find a 16100-79135-83 picture (also referred to on MR2OC). TwosRUs isn't correct. Despite what MR2OC says, I'm starting to think the only option is to use a 3S water pump and hard pipes.
 

No . Sorry.  Only have part no. for the 1998 year gen 3.  3sge water pump. 16100-79226.
It has 22 teeth. Round profile. Genuine Toyota (Aisin).
I cant see the very slight increase in rotational speed of the pump being a problem so long as it mates up correctly to the other fixtures on the 5S block.  Cam timing can be compensated for at the cam pulley.
You really need someone who has done this conversion to chime in.

It won't bother the cam timing. What's wrong with a 3s water pump?

I suppose there's nothing wrong with the 3S pump as long as it fits (I'm yet to test fit everything to the block). I had just decided long ago to use a 5S as that seems like what yhe US guys always use, and it means I have 5S oil and water pumps. I also thought it might make things easier with the hard pipes being 5S Water pump, 5S hard pipes on 5S block. I also read somewhere the 3s pump has a water bypass hose coming out of the bottom and the 5s doesn't, which should be easy enoough for me to check as I have both handy.

Ive got a 3s pump on mine. I put a bung on the barb that is related to the oil warmer/cooler. I've used all 3s bypass pipes.