Type VII U Boat References:

Lets make sure we are all singing from the same hymn book.

The U-505 was a Type IX U-boat, larger than the Type VII. 

Revell made a couple of 1:125 scale Type VIIB U-boats,  sold as the U-47 (Gunter Prein) and U-99 (cutaway).   The Type VIIB had a single-level conning tower.   The U-505 had a two-level tower with a 37mm on the lower.  A VIIB can be easily differentiated from a VIIC by the direction of the slant of the trailing edge of the conning tower.  On a B it slants forward top to bottom.   On a C it slants aft top to bottom.   There are also some minor length and torpedo configurations to deal with.

IIRC,  Monogram made a "Wolfpack U-Boat" which they sold as the U-505.   I forget the scale right now.   Any resemblence it bore with the real U-505 was purely accidental.  Revell may have obtained the molds to the kit when they and Monogram merged a dozen or so years back.   Regardless, the kit is 60s technology.

Your best bet for the sort of detail drawings you seek may be contained in "The Anatomy of the Ship - Type VII U-Boat"  by David Westwood or in the Scheiffer Publications title on the Type VII U-Boat 

A great source of info is http://www.uboat.net and it's links.

Good Luck

Thanks for the detailed info on this; especially the tips on telling a VIIB from a C (regarding slant on the conning tower).  I have been able to get a couple books on U-boat variants since my first post, one of which is the book you mentioned as well as one in German that have scaled-down blueprints. 

 Being an armor/figure modeler for the most part I should have known that the boats would have as many variants as tanks but am still surprised by just how many there were and the small details that changed!  It will be a test of my research skills jumping into this new realm and your post has definitely helped!