the top of the inectors are different as well. As in threads are different and the actual line size is different as well. i know cuz i just got done pullin out injectors of my 90 VE and my normal puller was wrong s i had to borrow a puller from my dad. And the pop off pressures and the pressure the VE puts out compared to the P7100 will be different as well. Just consider this, a P7100 can have 45 PSI of pressure feeding it were as a VE can have a max of 13 PSI.
i know but they wee talkin bout re-usin the VE injectors. atleast thats the way i understood it
on edit: You need front cover, lines, cam gear, INJECTORS, pump, and necassary safety features and accordin to the Cummins mech i spoke with last year the VE heads are supposed to be weaker than the P7100 era heads. Vacuum pumps are not the same. but should work with the right adapters.