Originally Posted by: GuitardedGeezer
I have a strat type neck, 21 frets, rosewood fretboard, truss rod already installed, and a paddle head. Also is a 21 by 14 by 1 7/8th block of kiln dried ash.

I've decided on a V shape, which I have sketched out on the block, as big as I could get it (still seems more narrow than a Gibson).
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The '58 is, I think, about 17" from tip to tip. Doesn't matter if you aren't making a replica :)

Originally Posted by: GuitardedGeezer
does anyone have any info on how to route the cavities for the humbuckers and pots from the back?
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You won't need to route for the HB's from the back. This will be the same with or without a pickguard. You route the front and mount them in rings. You could mount them directly to the body, too, but it's still a front route. Trace your HB & make a template or purchase one. I made my first ones, but it's hard to be machine-accurate. Not as important if it's going to be covered by a ring or pickguard. My next order is going to include some pup templates.

Originally Posted by: GuitardedGeezer
Also, what about the mounting the pots from the back? How much thickness do I leave between the cavity bottom and the front face of the guitar? Are there pots with long arms to reach farther?

Should be about 1/4 of an inch. You can get pots with longer post for this type of job.

[QUOTE=GuitardedGeezer]
Is there a place where I can get templates or something to help out with placement of everything? Which type of pot (250 or 500) should I use?

Generally speaking 250k for SC's, 500' for HB's. (Passives)

[QUOTE=GuitardedGeezer]
Also, I marked the spot for the tunomatic bridge at the 25.5 inch mark. How far back should I drill the holes for the strings to pass through the body? Does it make a difference? Any hints/tips on installing ferrules? seems like it would be easy to screw that up so the strings don't go though easily etc.

Good question as it is something I've been thinking about. I'm not sure I would go with string thru on a TOM bridge, unless I was sure the strings would not touch against the bridge on the way to the body. This was my original plan for my next guitar, but I've developed concerns about that. Maybe someone can shed some light? All I know on this is that even using a stopbar, if it's screwed down to low, the strings go down against the back of the bridge. That can't be good.

(But I know there are tons of TOM guitars out there that are string thru, I don't have one to look at. Maybe it's no big deal...?)

Alternately, there are string thru bridges, such as Fender Hardtail you could also consider.

You could try Stewart-Macdonald for some templates and also for some free information. They have calculators, for example to tell you exactly where to place your bridge and some cool stuff like that. It's a good place to start.