Switchless JiffyDos replacement rom for
Commodore 64 Breadbin (Longboard)
Switch between the original C64 kernal and Jiffydos Kernels
Default is Jiffydos. If you want to switch back to original rom hold the restore key while switching on the Commodore 64

Just remove the IC at U4 , then plug this switchless JIFFYDOS board into the socket at U4.
If U4 does not have a socket you will need to install a chip socket for easy installation.

Once installed you will need to solder the 2 wires to the restore and reset lines of the Commodore 64.

This is for a 24 pin rom socket. If your C64 has a 28 pin chip in U4 you will need to buy the shortboard version of the chip.