Some users, in istallation time, see so error:
JInstaller::install: SQL Error. DB function failed with error number 1074
Column length too big for column .. (max = 255); use BLOB or TEXT instead

Values in VARCHAR columns are variable-length strings. The length can be specified as a value from 0 to 255 before MySQL 5.0.3, and 0 to 65,535 in 5.0.3 and later versions.
In your case, Mysql version is less than 5.0.3 so max value = 255. You can change like that: in Com_vehiclemanager package, you opens vehiclemanager.xml file and replace:

all varchar(450) to varchar(255)

after that again do zip all files to package and try reinstall package again.

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