Allen engine analyzer scope and gas bench

Anybody out there have an Allen System Diagnostic III engine ****yzer with an ignition scope and exhaust ****yzer? I ask because I have one and am wondering if there are any other dinosaur owners like me. Looking to see if it makes sense to rebuild and make the exhaust ****yzer work or if it's even worth messing with. Just looking to discuss and share experience. Thx for any input or referrals.