The longest bolt needed is a pair of 5/16-18 thread in 6.75". Common hardware sizing is 6" and 8". A 7" will work...but you will need to order it from a fastner company.
Goodluck
If the 94 is a non abs model. Use the rear fitting on the SN95 proportioning valve on your Fox prop. valve and use the driver side brake line from the SN95.
This is the way the factory did the SVO. Much more reliable than a leaky 3-2 port converision. Only one fitting to swap and one brake...
My understanding is that you cannot use 98+ boosters due to the eyehole rod pointing straight out. Will not work with stock fox pedals. I used an 95 booster combo. I enlarged one of the bolt holes. Use ratcheting wrenches to make life easier.
Rick