I have for sale a Custom Downrigger base for trolling. This will accept (4) downriggers, more rod holders and your electronics. It is nice to have electronics in the back of the boat as well as the front. You can see depths changing from in the back and quickly adjust your downrigger depth. The measurements are all in the photos but I will list them also. The total length of the top platform is 77. The top tube is 7″x 1 7/8″. Total length from front to back is 28 1/2. The total height is 14. The base plates are 22″x 6″ tapered to 1. On the mounting bases outside to outside on the front (Towards the front of the boat) is 64 1/2. Outside to outside on the back of mounting bases is 63 1/2.