Hi Henry,
If the donor truck was a 8 cyl, you'll need to get a calpak from a 6 cyl truck, or the limp-home mode won't work correctly, among other tidbits. nce you have a HEI, switching it over to a computer controlled timing is a matter of wiring in the control mudule from a 88-92 4.3. Do you know what the codes are on the outside of your ECM? What year truck and engine model is the donor?
MV
