My last jig was destroyed when the depth locking mechanism decided to crap out on my plunge router, so I decided to go all out and build this one based on David Myka's:
The rear rail support is vertically adjustable, so it's capable of routing angles from 0° to 3.5°.
The rails are from an old server rack that I was using for shelving. I got the self-adhesive rules and knobs in a kit from Rockler, and the T-slots and holddowns from Harbor Freight. The base is made from 2 layers of 1/2" MDF, the rear rail support is Maple, and the front rail supports are Sapele, all pulled from the cutoff bin.
All said and done, it cost me about $30 above what I had on hand, and took about 4 hours to complete. Not bad for an afternoon
I'm going to be building a run of 4 guitars starting next week, so we'll see how it performs.
Thanks for looking!