Notice:
The advice given on this site is based upon individual or quoted experience, yours may differ.
The Officers, Staff and members of this site only provide information based upon the concept that anyone utilizing this information does so at their own risk and holds harmless all contributors to this site.
Mast length is the key. I *believe* the SR is 28' and the TR is 30'. If you have a 100' fibreglass tape (available at Home depot for about $30) you can tie it to the end of the halyard and measure by raising it to the top of the mast.
You can measure the mast with a 30 foot long rope or sturdy cord you attach to the halyard. Hoist it aloft, mark the bottom at the foot of the mast, and measure it conveniently with any measuring device after lowering it. 28 feet = SR 30 feet = TR
Having made this mistake recently, I can attest to how easy it is to do. The easiest, fastest, most accurate way to determine is to run a long tape up to the mast head. A SR has a 28' mast and a TR has a 30' mast. The extrusions are a little different (the SR has a more squared off extrusion whereas the TR is more rounded), but is hard to tell without both examples handy.
Get a tape measure, a string, a garden hose, and extension cord, anything handy and run up the halyard. Measure. There's your unequivocal answer.
P.S. Measure BEFORE you buy any sails. You'll be glad you did. Don't ask me how I know this.
Dave was half joking when he mentioned just swing the boom and see if it knocks you senseless. But there is some truth to that. I'm 5' 10" and it won't hit my head but it will come close. Obviously, the best way to to tell is to attach a line to the shackle on the halyard and raise it to the top, then note where the attached line comes to at the base of the mast. Then when you pull the shackle back down, you can measure the length of the attached line.
But the 30' foot mast, tall rig, has the boom located lower on the mast. For example, those that have installed a Bimini are mostly those that have the standard rig. On the tall rig, the boom is pretty low and there is not much clearance to install a Bimini. I believe some of the earlier Cat 25s with a tall rig, the boom was not attached to the mast at a fixed point, so it may be possible to install a Bimini on a tall rig...but it's a close fit for anyone under the Bimini and the Bimini not touching the boom. On my '89 tall rig, a Bimini is not really feasible. My boom is mounted to the mast at a fixed location and a Bimini would have to be so low in the cockpit, that I would then probably have to duck under it.
So, if you can picture a Bimini having enough clearance under the boom, then it's probably a standard rig. If a Bimin looks like it's going to be a real tight fit under the boom, then it's most likely a tall rig.
Notice: The advice given on this site is based upon individual or quoted experience, yours may differ. The Officers, Staff and members of this site only provide information based upon the concept that anyone utilizing this information does so at their own risk and holds harmless all contributors to this site.