I did the swap with 95/96 T100 3.4 engine about 10 yrs ago.
I have head gasket issue now. Tried BlueDevil but it didn't work.
I was wondering if I can keep the 3 wire throttle body or the whole intake and get a newer block.

 

Any 5vzfe 3.4 should have the block and heads you need, but you'll want to strip everything off of your existing engine to put on the replacement since wiring and sensors changed from year to year.
IMHO you'd be better off doing head gaskets.

 

You're probably right. I'd thought I'd see if someone have other ideas.
It's been good for almost 10 yrs.