Jeff,
The 216 I believe is the same length as the 235 which is an inch plus shorter than the original 206. Can you tell how the cross frames were modified ?
On the battery cable, are you running a 6 or 12 volt starter ? The 6 will require a larger wire. Lenght should not be an issue going to the firewall.I just go by eye with what I have around but will see if I can pin down some actual recommended sizes.