How difficult to fix 4kq speedo?

[TM]

Listers,
Having no experience with the 4kq (other than driving one), how
difficult is it to fix the odometer/speedometer in a 4kq? Is it
the same plastic gear issue as the 5k? Can the parts be obtained
new or does one have to scrounge for a replacement at the junkyard?

What about stuff like the blower motor and the heater core? Are they
difficult to replace on the 4k?

Thanks.

Taka