The link you provided says
"This system includes a complete TBI conversion plus a custom HEI distributor for complete fuel and spark control."
I'm thinking your opening a can of worms if you don't use their "custom HEI". Whether they have one or not for a 250 is a another question. I have a 4.3 distributor I think and there is a difference in shaft lengths. I have to look at again to see if it could be made to work, but if they are supplying the distributor there is a reason. Let me know if that 4.3 distr will help.
Larry
