uh, well personally i think that if you're confident in your abilities there's no need bother with a kit.
I bought 2 sheets of plexiglas @ $2.00 ea
and then door moulding @ $4.00
got the plexi at home depot, and 2 2-foot door moulding strips at an auto supply store. Total funds: eight bucks, no shipping.
Then I got a friend with an arc cutter to cut the window out, sanded and painted it, threw the moulding on and then used some double stick tape to hold the window up.
i'd say take the side off, cover it with tape, trace your cut pattern on it, then dremel it (or have someone do it for you) then put your moulding on if you're not painting it and you're good to go.
save yourself a few bucks, and the outcome will be the same. good luck!