next step air fuel ratio meter or

i'm running a 750 dbl pumper on a 30 over stock build 360 with every bolt on.the only thing left to do is crank, rods, and pistons.
the car runs tits, but i get worried running it past 5 grand. it does have the stock 5/16 fuel line and to me seems to lean out up top (starts to miss sumtimes). a fuel pump and new lines are in the work.(any suggestions)
now an air fuel ratio meter sounds like my best bet or is it just a waste of alot of money. i do have an extra spot in my new dash for an extra meter and was torn between air fuel or trans temp.
this is a street strip car and for now a daily driver. the stroker kit in the next year, for now just getting ready.

727, cheeta valve body w/shift kit
3800-4200 converter w/ b&m trans cooler
4:11 moser 60
10.5 mickey street ets
comps slide a link traction bars
3 in. x pipes w/3 in. tti's
msd e-curve distributer w/coil only
mighty demon 750
m-1 intake
stock eddy heads w/ thin gasket and 1.5 rollers
480-480 lunati cam
4 core w/ electric fans
fuel cell and batt. in trunk

so before i go wrench her down the track i want to make sure she's tuned right. i really dont want to make 20 passes just to get it dialed in.

what would you do to this dart? 11 sec. here i come.

thanks abodyhotrod