if you can purchas a battery gig.. this will help keep your cells straight while you solder them togather .. while in the battery gig . make sure the cells are in neg side up . then the next cell pos side up and so on .. make sure you use at least a 40w iron and LET THE SOLDER TO THE WORK !!! you want to use a small amount of solder ,, enough to hold the battery bars in place .. just remember ,,, dont get the cells to hott .. this can damage your cells ,,, after you have the battery pak assembled let it sit a few minutes then add your wiring again dont let your battery get to hott ... you should be fine at this point ... let the battery cool about 5 minutes then charge it up .. !!!
have fun at the races ... mb.