How do you change spark plugs on a 2007 Yamaha phazer?

First you have to remove the seat and tank.

1 Seat 1

2 Rear cover 1

3 Plastic band 4

4 Tail/brake light coupler 1 Disconnect.

5 Tail/brake light assembly 1

6 Main switch coupler 1 Disconnect.

7 Fuel tank cover 1

8 Fuel pump coupler 1 Disconnect.

9 Fuel hose connector holder 1

10 Fuel hose 1 Disconnect.

11 Plastic band 6

12 Fuel tank assembly 1

13 Fuel sender coupler 1 Disconnect.

14 Fuel hose 2 Disconnect.

15 Fuel pump 1

16 Fuel tank lower plate 1

For installation, reverse the removal procedure

From there...you should be able to handle it.