Toy train operating and collecting

So, I have this plastic flat bed semi trailer that I want to shorten. It is about 2 3/8 inches wide. I figure I can just use a miter box and a razor saw to cut out a middle section and then glue back to gether. No big deal right? Well I'll be danged if I can find a miter box wide enough. At least that will allow use of a razor saw. Yeah I can get one at Lowe's or Home Depot but they are made for a miter saw which I am afraid to use. Not sure I can get a super clean cut in the plastic and if I try and use a razor saw in it, I am afaraid there will be too much "sloop" and I will wind up with a bad cut. I have tried 2 or 3 hobby stores. I even tried our loacal wood crafters store! I do not have access to a scroll saw or any other power tool that would have a fence or square so that I can get a square and true cut.

Can any body help me out here with a suggestion or someplace I can go and have it cut?

As usual, Thanks guys for all the help!

Ken

Are you familiar with this trick?  Cut it as well as you can, perhaps with the big miter box.  Then butt the two pieces together and clamp them to a board.  (I am assuming that the trailer bed is flat enough for you to do this.)  Then cut the butt joint apart again with your razer saw.  Loosen the clamps and close up the resulting kerf again.  Keep cutting at the joint and reclamping until any irregularities left by the first saw are gone.  Then glue it together, of course.

 Why don't you just make your own miter box.  It is simple to do.

Earl

EIS2:

 Why don't you just make your own miter box.  It is simple to do.

Earl

Ken

Use a square to mark your cuts and carefully cut along your lines. 

DennisB-1:

Use a square to mark your cuts and carefully cut along your lines. 

Thanks everyone!

I'm glad that worked out for you, Strogey.