Blow thru gap filler options?

Okay so don't judge me but I bought my truck with a hole in the back of the cab and front of bed... You get the point so they had it sealed to the cab with plywood and wood screws I know I know it was my mistake anyhow I've decided to go with a correct blow thru and my question is how to deal the space between the cab and bed. And I know many people use accordion boot and I may but I would like to find something cheaper if possible... Sorry kinda Ramblin I work nights and I'm tired as sh** any input would be great and one more thing I am set on the blow thru idea and I don't have access access to a welder.

cheap isn't good, good isn't cheap

What size is the hole? How about an inflatable boot.

Well I'll see if I can get a decent picture at some point in the next few days but I checked out that Site, Ulrich, and I may be able to afford the accordion boot after all ebay and amazon sold it for like $80... Thanks again and I'll try to keep everyone posted

I had a truck that had about a 24x12 hole in the cab and the bed for a sub box in the bed. I got a large inner-tube from my buddy at les schwab. I cut it down the seam, laid a thick bead of silicone on the inside of the cab and screwed the inner-tube down. I did the same in the bed. I then put the sub box into the bed and made a carpeted beauty panel with grill for the speakers. The homemade boot worked great, never leaked, and was hidden by my cover and sub box. The key is to use a ton of silicone before and after the boot install to prevent any rain from sneaking in.

my truck has a blowthru. I used a joebox and cut the doors off then welded it to my cab. I used a seam sealer. It also doesnt go bing bang bing when the BASS hits. Best thing if you dont want it though id recommend using the welder and a flat sheet of sheet metal cut to fit your hole. If you plan a blow through then use mdf perfectly cut to fit and then rhino line the sub box or water damage would hurt. I have two kicker comp 12s and a 1000watts... not much but i plan on goin to 10,000 watts.-kyllo

Do it right and use the accordion boot.