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...from what I remember, it was around 1/4" and the mirror's minor axis is 1.4"...

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The correct offset at f/5 with a 1.4-inch minor axis secondary mirror is about 0.07-inch. If you had left the offset at 0.25-inch, and used a standard offset alignment procedure--the optical axis would have ended up about 0.18-inch offset away from the focuser. OTOH, if you remount the secondary mirror so that it's mechanically centered, and you use a standard offset alignment procedure--the optical axis will end up 0.07-inch closer to the focuser. Either way, I doubt you will notice any difference in the optical performance.

If you choose to offset the secondary mirror correctly, and the mounting stalk is 1.25-inch--the 0.07-inch offset (with a 1.4-inch minor axis) will reduce the overhang on the side closest to the focuser to less than 0.01-inch and increase the overhang on the side away from the focuser to almost 0.15-inch. It will look a little strange... but it does deliver the optimal placement for the secondary mirror. Of course, you could also decenter the primary mirror and/or the spider and arrive at an almost identical placement.

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