No need for the vac pump in that case.

ok thank you. also as far as my ip and ip lines is us diesel a good source for the ip and lines

I honestly don't know who to send you to for an IP,lines can be had almost anywhere though.

The 6.5 injectors would also have to be used as their shorter for turbo clearance

the 1991 injectors are the same size on mine it all fits. cant tell its a 6.2 unless you know what to look for.

the 6.5l i had in my truck originally had new Bosch hi flo injectors on it. Should i Run these with the 6.2l, instead of the 6.2l injectors. The 6.2l injectors are the shorts and as far as fitting the turbo they work. but when i took of lines i noticed they were rusty and the original ones. the engine has 175,000 miles. If i run the hi-flo's, will they work with my pump? I'm building for mileage not power. Also thank you for all the input.

The high flows will work fine.

If you mean marine injectors when you say high flow-they will be no problem but are no advantage at all without the marine IP pushing the fuel.
The IP is the bottleneck in the system,stock injectors will flow more fuel than the IP can send so I discourage people from buying marine injectors thinking they will get 40 more HP-they won't if that is the only upgrade.

I have the papers from the shop it before i bought it and it says Bosch Hi-Flo Injectors, Cradled main caps, Cry O2, Heath Heads, Max E Tork Prom, and bored .10 over. I just found it couple days ago in a folder he gave me. I guess he tried making a pulling truck and realized it couldn't compete with the big 3. The only reason i was contemplating swapping out injectors was only for the fact that they are newer. and the 6.2's look pretty ragged. and i have to replace the o rings in the 6.2 anyway.

The 6.5 injectors will work just fine provided the heads accept them,some are fine thread,some are coarse?

ok, also what exactly is cry o2, i heard some good bout it and some bad.