Hi - First time poster here. I'm doing a Cummins 4BT swap into a 1990 F150 extended cab 4x4. This will be pretty much a highway queen, no serious off- road. I'm going to run 305/85/16 Denman Coyotes to get the overall gearing I want. Its getting a '79 D44 front along with 9" rear. I'm planning on using 4" TTB coils and the stock TTB buckets along with a 1" body lift. I need the body lift for clearance for the downpipe for the high mount turbo or take a hammer and torch to the firewall. Can someone recommend what coils to get? The 4BT weighs approx 225 lb more than the 5.0 that came out. I don't need a lot of flex for this duty but I want something heavier than the stock. I was browsing someone's catalog tonight and saw some 4" coils for the 1984 150 with the big block, do you think those would work? I'll be using the stock '79 arms. Will the 4"+1" work ok with the narrow 36's for the pavement? Thanks.