Generally the mid-’90s transitioned to a computer more like this. The computers were sealed with O-rings and/or gaskets, usually got heat sinks to help with cooling, and were most often found under the hood. This is an OBDI Chevy computer, but many of them (even early OBDII) were this size and shape. Jeep computers of this period were about the same size, but had many more vents on them and were painted black. Notice the two small vents this one has for cooling (arrows). If possible, it is best to mount the computer with the vents facing towards the firewall, but leave some breathing room.