We have new MEFI 4B ECU's to upgrade the older MEFI 1,2,3 ECU's. Mefi 4B ECU's are Marine grade to withstand harsh envioroments, high shock loads and wet conditions. Re-pining the J1 & J2 wiring harness connectors is necessary. Included is the pin-out conversion chart (optional J1 & J2 connectors are avilable). If you don't see what you're looking for please call or e-mail us. Phone: (480) 753-0208 Fax: (480) 753-0216 Hours: 8am - 5pm M-F Mountain Standard Time