1981 Mazda 3 I keep cracking the back of my head on the sid

I'm retired and a lot of spare time, except for answering questions on the forum, so I took this old Mazda and shortened up the wheel base about 2 ft. Over in the corner of the garage I had this old 392 hemi, trans and rearend so, I welded that all in and actually got it running. It's not street legal so I use the sidewalk. BUT, problem is, when I rev it a little bit and dump the clutch, it rears up and I hit my head on the sidewalk. I've got an old bed frame with casters on it and was thinking about making me a set of them wheely bars. Do think that will help?
THE JIG IS UP GUYS, This is moderator James R. Weizel, I'm going to change my user name when I get around to it. ANYWAY, I just set this posting up to experiment with down loading pictures, diagrams and text, so don't pay any attention to it unless you want a good laugh now and then. I'll keep it answered so it doesn't take up space on the donor page. Also, if you believed the part about the Mazda and the Hemi, I, ve got a bridge in New York you might want'a buy. Best to ya, you guys do a great job and there's a lot of grateful people out there.