[mr48chev]

Mar-K doesn't give an exact board width for "their" boards but the measurements are for 1/2 inch gaps between the boards while I'd think the ones on Classic Heartbeat are for more like a 3/8 gap. You don't want the boards butt up against each other or butt up against the bolts as that won't leave any room for swelling or shrinking. That isn't as big a deal with most show only trucks but could be a big issue with a daily driver that gets wet more often.

As long as you didn't cut all the boards too narrow you should be fine. lay in the outside boards and the ones next to them and lay the strips on them and go until you get to the last board. leave everything loose so you can do some adjusting and then see if you have to modify the last board to get things to work. If you do have to alter the last board a bit only you will know and anyone that figures it out is looking way too close anyhow.