What order do I do this in? cowl or firewall

[rusty1970]

 

[rusty1970]

Which do I put in or replace first.  Full cowl, or after replacing torque boxes the firewall and floor extensions?

[sigtauenus]

The cowl welds to the top of the firewall.  If the firewall is installed incorrectly, your cowl won't sit right and you will have alignment issues with the hood and fenders and doors.

The best way to do this, although most time consuming, is to mock it up first.  Place your floor extensions and firewall into position and drill some 1/8" holes and screw them down to hold in place.  Then set the cowl in position and do the same.  If you are really feeling snazzy, install the hood and fenders and make sure they align with the cowl.  If they don't, now would be the time to find it and fix the panel alignment.  What I'm describing is very painful, but it ensures everything will line up correctly when its done.

I think it will be easier to weld the firewall in first, then the cowl.  Once everything is welded, it would be a good idea to put those fenders and hood back on to double check your work - better to find the problem now than after you've started spraying paint.