68 hemi dart build

I am building a 68 hemi dart race car and I live in north carolina. the car does no need to run faster than 6.0 in the 1/8. 4sp cal tracks ford 9 inch in place on car weight 3100 who would you guys advise to build engine. would it be best to modify k frame or buy tubular K frame if so what brand


thanks for the help