73-80 to 81-91 Front End Conversion

[JCampbell]

I've heard inconsistent smatterings of rather ambiguous info regarding the need to modify the front frame horns when dropping a 81-91 front clip onto a 73-80 truck.

I always thought said conversion was, for the most part, "bolt-on" (aside from notching the cowl for the hood hinges). What's the deal? Do the frame horns need modification, too? Anybody have pics? I'd rather do it now while I have a bare frame sitting in the garage, than fight with it later.

[Dalaigh]

Heres are pics of the difference
1973-80

81-91

and where you need to cut, to make the 81-91 front end fit

Then the bushings are different as well, but I think the bushings for the year of the frame will work, with the 81+ front end.

[wilkin250r]

VERY INTERESTED!!! I've actually got one of these, but the conversion was done before I acquired it, so I don't really have any details of the conversion process. But I'm interested in knowing the details of the hood. The 73-80 hood comes all the way back to the windsheild, the later years have a panel about 8 inches wide between the hood and windshield.

So what I've got is a short hood and a 8-inch gap between my hood and windshield. So I've got one of two choices, either fabricate a custom hood that has the front portion of the one style, and the rear portion of another, or find a way to mount that panel, probably welding some tabs to mount it to.

What I CAN offer is pictures of my truck and what has already been done. But I they're crappy, all the welds look terrible, it's not lined up very well, I don't know if they'll be of much use.

EDIT: Sure enough, after seeing those pictures, my front frame horns are cut. However, mine weren't cut at an angle like the pictures, mine are cut square, hacked off with just enough room to utilize the bolt hole on the top there.

[Dalaigh]

What you need is to find a cowl from an 81+ truck, then once you set it in place you'll see where you need to drill holes. The cowls are set in to holes up by the window and screwed to the firewall at the bottom, just below the hood.
Like this

and you will need to indent the edge for the washer fluid squirter

You can see where the hole in the fender needs to be for the hood hinge.

For the most part it is a bolt on process, but there is some fab work. It's a lot easier the go from 81+ front end to 73-80 front end.

[Dalaigh]

You also need to swap over the 81+ wiper rotating assembly, the 73-80's are too short for the cowl panel, and if going the other way the 81+ rotating assembly is to tall for the 73-80 hoods.

[N2TRUX]

You might want to look at this before cutting your frame- LINK

[JCampbell]

Originally Posted by N2TRUX

You might want to look at this before cutting your frame- LINK

Good to know. Thanks.

[gchemist]

I did my conversion following this article: http://coloradok5.com/grilleswap.shtml

My old website was taken down. I had some really nice conversion pictures. I need to get them off my old computer and put up again.