Take I-80 west to I-380 north(approx. 20-25 miles) till you get to Hwy 30. Take hwy 30 east (3 to 5 miles) till you get to hwy 13 north you'll come across 4 stop signs on hwy 13 N on the 4th 4 way stop turn right on to County Home Rd. (also known as E34) go for 3 to 5 miles till you come into Whittier (really small town) with one stop sign. At this stop sign take a left and go drive till it looks like your heading out of town(about 2 blocks) and Larry Johnsons place is on the right (you'll be able to tell by all the Fieros parked in his yard).
Let me know if you need anymore help!!
I'll P.M. you my home phone and cell phone if that'll help.
Cya there,
Dan
P.S. A short cut would be to take HWY 1 north(it's on the east side of Iowa City) to (approx. 16 miles) Mt. Vernon(hwy 30) and turn left(west) at the 4 way stop on Hwy 30 to Hwy 13 North then as above to Larry's place. It's a little shorter but involves some 2 lane as opposed to 99% 4 lane.