Well I got the valve today. It's a 5-way pneumatic valve made by Norgren and looks like it'll do the job for replacing my solenoids. Tomorrow and Saturday I'll be working on the conversion and if everything goes well, I'll post a writeup on how to do it, complete with pics and part numbers. This valve looks pretty stout and should hold out for a good long time. It's a toggle, but unfortunately the toggle itself is too large to put any kind of switch guard on it.
I have one problem though, and that's figuring out how exactly I'm going to route the vacuum lines into the cabin (dash area specifically). I'm thinking I won't be able to get out of drilling my firewall this time, so what are some safe spots to drill it from the side of the engine compartment where I won't have to worry about damaging anything? Or, any suggestions that'll avoid me having to drill would be even better.
I have one problem though, and that's figuring out how exactly I'm going to route the vacuum lines into the cabin (dash area specifically). I'm thinking I won't be able to get out of drilling my firewall this time, so what are some safe spots to drill it from the side of the engine compartment where I won't have to worry about damaging anything? Or, any suggestions that'll avoid me having to drill would be even better.